chromium/third_party/blink/web_tests/fast/loader/resources/onunload-form-submit-failure.html

<html>
    <head>
        <script>
            function continueTestAfterNavigation()
            {
                if (window.testRunner)
                    testRunner.notifyDone();
            }
        </script>
    </head>

    <body onload="continueTestAfterNavigation()">
        <p>Bug: rdar://problem/4268278 Submitting a form in onUnload event handler causes crash in -[WebDocumentLoader(WebPrivate) _commitIfReady:]</p> 
        <p>If this test passes, you'll see a PASS message below.</p>
        <hr>
        <p>FAIL: You should not reach this page any more, since a form submission in an onunload handler has no effect.</p>
    </body>
<html>